This invention relates generally to seed planter press wheels of the type typically used on agricultural planters. More specifically the invention relates to seed planter press wheels which are self cleaning and inhibit the sticking of any caked mud on the outer surface of the press wheel.
The use of seed planter press wheels on planters is well known in the art. Typically the press wheels compact the soil over seeds deposited in the earth. The use of a press wheel which compacts the soil promotes the seed germination by retaining moisture in the soil and by maintaining the seed in close contact with the earth. Present planter press wheels compact and mold the seed bed to assist in good germination.
Because an adequate amount of moisture is necessary to promote germination, planting is best accomplished when adequate moisture is contained in the soil. However in such situations due to wetness of the soil and the sticky nature of the type of soil, the soil tends to cake up and pack on planter press wheels. There are times when it is desirable to plant seeds due to the favorable germination conditions and climate conditions although the soil conditions are such that caking and balling of the soil may prevent planting.
Over a period of many years, others have attempted to solve the problem of caking of mud on planter press wheels. An example of this is shown in U.S. Pat. No. 2,249,637 issued to E. L. Rietz which discloses a planter press wheel having annular tires. The tires are disclosed as being made of rubber which is flexible so that it will not accumulate soil and will be self-cleaning. Apparently, Reitz discloses a pressure tire since mention is made of an inner tube.
U.S. Pat. No. 2,691,335 issued to S. E. Murray also discloses a pneumatic planter press wheel. Murray discloses that the resilience of the tire will provide a self-cleaning action to remove soil tending to cling to it. Murray also discloses that the type of tire used makes it possible to support the planter over highways. The tire of Murray is filled with air greater than the atmospheric pressure which is disclosed as providing substantial flexing of the sidewalls, tread portions and inwardly converging walls in loose soil.
U.S. Pat. No. 2,698,566 issued to C. R. Stough discloses a wheel for receiving two hollow rubber tires. The tires are disclosed as having an air space and it is assumed that the tires would be flexible since they are made of rubber and include the air space.
U.S. Pat. No. 2,703,517 issued to J. M. Hooper discloses a pneumatic planter press wheel. Hooper discloses that in wet soil where the earth has a tendency to stick to the planter wheels the tire presents a smooth, highly flexible tread surface and flared sidewall surfaces to which the soil does not easily adhere. A valve stem 24 is provided in Hooper to supply air to the tire.
U.S. Pat. No. 2,731,900 issued to W. P. Oehler discloses a zero pressure rubber tired planter press wheel. Since the tire of Oehler is made of rubber, it is assumed that it would exhibit flexing upon contact with the earth.
U.S. Pat. No. 3,181,622 issued to C. B. Adams et al discloses a rubber planter press wheel having an outer tire member at zero pressure (atmospheric pressure). Adams et al discloses that the tire flexes thereby expelling any ground tending to cling to the tire surface. Adams et al also discloses that the degree of flexing is slight in comparison to other rubber tired press wheels thereby increasing the service life of the tire. Adams et al also discloses a planter press wheel having a resilient cover member which flexes to reduce adherence of soil.
U.S. Pat. No. 3,207,234 issued to W. R. Stewart discloses a planter press wheel which is of the zero pressure type. Stewart discloses that it has been known to provide a semi-pneumatic tire for a planter press wheel so that the tire would flex as the wheel rolled over the ground to break up moist soil and remove it from the peripheral surface of the tire.
As shown by the above prior art, numerous attempts have been made to solve the long standing problem of soil sticking to planter press wheels. Notwithstanding these attempts, the problem still exists whereby in certain conditions the soil will stick to the planter press wheel and prevent operation of the planter. There is a long felt need for a planter press wheel which can be used in adverse soil conditions whereby it is desirable to plant a crop. When the soil conditions prevent planting this may be costly in that delays are incurred involving shutdown time and which also may involve detrimental consequences later when the crop does not have a full growing season or is not planted at a time to take advantage of the optimum germination conditions and growing season.
It is an object of the invention to overcome the problems in the prior art by providing a planter press wheel which does highly inhibit the caking of soil thereon in adverse conditions which has not been satisfactorily achieved by the prior art press wheels. It is a further object of the invention to provide a planter press wheel which will properly compact the seed bed to facilitate germination while at the same time permit planting in adverse soil conditions without excess caking and balling up with mud. Further objects of the invention will become apparent from the following detailed disclosure.